Posterior Abdominal Wall

Question 1

Psoas major

Answer 1

Superior attachment: transverse processes of lumbar vertebrae; sides of bodies of T12-S1 vertebrae and intervening IV discs
Inferior attachment: by a strong tendon to lesser trochanter of femur
Action: acting inferiorly with iliacus, flexes thigh; acting superiorly, laterally flexes vertebral column to balance trunk; when sitting, acts inferiorly with iliacus to flex trunk
Innervation: lumbar plexus via anterior branches of nerves L2-L4

Question 2

Psoas minor

Answer 2

Superior attachment:

Question 3

Iliacus

Answer 3

Superior attachment: superior 2/3 of iliac fossa; ala of sacrum; anterior sacro-iliac ligaments
Inferior attachment: lesser trochanter of femur and shaft inferior to it; psoas major tendon
Action: flexes thigh; stabilizes hip joint; acts with psoas major
Innervation: femoral nerve (L2-L4)

Question 4

Quadratus lumborum

Answer 4

Superior attachment: medial 1/2 of inferior border of 12th rib; tips of lumbar transverse processes
Inferior attachment: iliolumbar ligament; internal lip of iliac crest
Action: extends and laterally flexes vertebral column; fixes 12th rib during inspiration
Innervation: anterior branches of T12 and L1-L4 nerves

Question 5

Diaphragm (crura)
Arise from:
Right crus: 
Left crus: 
United by:

Answer 5

Arise from: anterior surfaces of bodies of superior 3 lumbar vertebrae, anterior longitudinal ligament and IV discs
Right crus- arises from 1st 3-4 lumbar vertebrae; left crus- arises from 1st 2-3 lumbar vertebrae
United by: median arcuate ligament

Question 6

Diaphragm (esophageal hiatus)
In:…
Transmits:
/

Answer 6

In muscle of right crus at level of T10 vertebra

Transmits: anterior and posterior vagal trunks, esophageal branches of left gastric vessels, few lymphatic vessels

Question 7

Diaphragm (aortic hiatus)
Opening:…
Transmits:

Answer 7

Opening posterior to diaphragm

Transmits: descending aorta, azygos vein, thoracic duct